The present invention relates to a printer for printing a color image and, more particularly, to an ink jet system printer of the ink-on-demand type for printing a color image.
Generally, in a color printer, various colors are formed by mixing three primary colors, yellow, magenta and cyan. A color ink jet system printer has been proposed, wherein the above-mentioned three color ink droplets are emitted from a printer head, and the color ink droplets are mixed on record receiving paper.
In the conventional color ink jet system printer of the ink-on-demand type, a plurality of orifices of different colors are directed to a single picture element position. This complicates the printer construction and, therefore, the conventional color on-demend ink jet system printer is not suited for multi-orifice construction.
In another conventional ink-on-demand color printer, a plurality of orifices of different colors are vertically aligned. In one type, a record receiving paper or a printer head is shifted in the vertical direction for each picture element in order to mix the different colors. This complicates the mechanism for driving the printer head of the record receiving paper. In another type, a first color is first printed by one line then a second color is printed on the same line after the printer head is returned to the initial position. This control lengthens a time period between the depositions of the first and second color droplets and, therefore, the colors are not properly mixed.
Accordingly, an object of the present invention is to provide a novel control system in a multi-orifice ink-on-demand ink jet system printer for printing a color image.
Another object of the present invention is to simplify construction of a color ink jet system printer.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
To achieve the above objects, pursuant to an embodiment of the present invention, a plurality of orifices of different colors are aligned in the horizontal direction on a printer head with a predetermined distance therebetween, and a control circuit functions to emit the ink droplets from the respective orifices at a preferred interval while the printer head travels in the horizontal direction.